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Zipper’s Muscle 124 Kit combines Big Bore with Big Stroke! At the bottom, a 4-5/8” stroke crankshaft paired with 4-1/8” cylinders establishes the base for 124” of Big Power. An engine this size needs specialized cylinder heads, Zipper’s ultra-high flow Stage IV CNC porting with highly modified chambers along with oversize, unshrouded valves delivers just that. New stress-relieved cylinders are precision-fit with durable forged pistons supplied with high quality 1-1-3mm rings. Red Shift 657 cams and dual-piston tensioners, Pro-Taper pushrods, longer head bolts and E-Z Adjust pushrod covers are provided with all the gaskets needed for assembly. Case boring required for 4-1/8” cylinders; Timken® bearing conversion, our blueprinted cam chest oil system upgrade for rock solid stability and durability are highly recommended. Show ‘em your rapidly fading tail light every pass, every time!
This kit uses your factory head cores sent in for modification. An exchange may be possible once your cores are cleaned, inspected and qualified for exchange.
Not legal for sale or use in California on any pollution controlled motor vehicle.
Not legal for sale or use on any EPA pollution controlled motor vehicle.
*To ensure you enjoy a premium experience, Please fill out a Build Sheet/Job Order Sheet prior to completing an order on the website.
Click here for Zipper’s Build Sheet/Job Order Sheet
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Zipper’s Muscle 124 Kit combines Big Bore with Big Stroke! At the bottom, a 4-5/8” stroke crankshaft paired with 4-1/8” cylinders establishes the base for 124” of Big Power. An engine this size needs specialized cylinder heads, Zipper’s ultra-high flow Stage IV CNC porting with highly modified chambers along with oversize, unshrouded valves delivers just that. New stress-relieved cylinders are precision-fit with durable forged pistons supplied with high quality 1-1-3mm rings. Red Shift 657 cams and dual-piston tensioners, Pro-Taper pushrods, longer head bolts and E-Z Adjust pushrod covers are provided with all the gaskets needed for assembly. Case boring required for 4-1/8” cylinders; Timken® bearing conversion, our blueprinted cam chest oil system upgrade for rock solid stability and durability are highly recommended. Show ‘em your rapidly fading tail light every pass, every time!
This kit uses your factory head cores sent in for modification. An exchange may be possible once your cores are cleaned, inspected and qualified for exchange.
Not legal for sale or use in California on any pollution controlled motor vehicle.
Not legal for sale or use on any EPA pollution controlled motor vehicle.
*To ensure you enjoy a premium experience, Please fill out a Build Sheet/Job Order Sheet prior to completing an order on the website.
Click here for Zipper’s Build Sheet/Job Order Sheet
Weight | 1 lbs |
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Related Parts | #417-498, #517-968, #517-969 |
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DW –
I cannot thank team Zippers for what the Muscle 124 Twin Cam kit has done for my motorcycle.
I have been riding motorcycles for 45 years and can honestly say that the ride with this engine kit is like none I have ever experienced. To feel the power and acceleration with just a twist of the throttle was incredible. When riding with friends they are amazed at how the quickly I can pulled away from everyone
The 124 muscle kit has made me the talk of the town Thanks to team Zippers for my new power. Cannot wait for my next cross country trip!
DW